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Commit | Line | Data |
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1b1a35ee XL |
1 | #[cfg(test)] |
2 | mod tests; | |
3 | ||
4 | use hashbrown::hash_set as base; | |
5 | ||
532ac7d7 | 6 | use crate::borrow::Borrow; |
e1599b0c | 7 | use crate::collections::TryReserveError; |
532ac7d7 | 8 | use crate::fmt; |
dfeec247 | 9 | use crate::hash::{BuildHasher, Hash}; |
532ac7d7 | 10 | use crate::iter::{Chain, FromIterator, FusedIterator}; |
dfeec247 | 11 | use crate::ops::{BitAnd, BitOr, BitXor, Sub}; |
1a4d82fc | 12 | |
1b1a35ee | 13 | use super::map::{map_try_reserve_error, RandomState}; |
1a4d82fc JJ |
14 | |
15 | // Future Optimization (FIXME!) | |
532ac7d7 | 16 | // ============================ |
1a4d82fc JJ |
17 | // |
18 | // Iteration over zero sized values is a noop. There is no need | |
19 | // for `bucket.val` in the case of HashSet. I suppose we would need HKT | |
20 | // to get rid of it properly. | |
21 | ||
cc61c64b | 22 | /// A hash set implemented as a `HashMap` where the value is `()`. |
d9579d0f | 23 | /// |
cc61c64b XL |
24 | /// As with the [`HashMap`] type, a `HashSet` requires that the elements |
25 | /// implement the [`Eq`] and [`Hash`] traits. This can frequently be achieved by | |
d9579d0f AL |
26 | /// using `#[derive(PartialEq, Eq, Hash)]`. If you implement these yourself, |
27 | /// it is important that the following property holds: | |
c34b1796 AL |
28 | /// |
29 | /// ```text | |
30 | /// k1 == k2 -> hash(k1) == hash(k2) | |
31 | /// ``` | |
32 | /// | |
33 | /// In other words, if two keys are equal, their hashes must be equal. | |
1a4d82fc | 34 | /// |
c34b1796 AL |
35 | /// |
36 | /// It is a logic error for an item to be modified in such a way that the | |
cc61c64b XL |
37 | /// item's hash, as determined by the [`Hash`] trait, or its equality, as |
38 | /// determined by the [`Eq`] trait, changes while it is in the set. This is | |
39 | /// normally only possible through [`Cell`], [`RefCell`], global state, I/O, or | |
c34b1796 AL |
40 | /// unsafe code. |
41 | /// | |
42 | /// # Examples | |
1a4d82fc JJ |
43 | /// |
44 | /// ``` | |
45 | /// use std::collections::HashSet; | |
46 | /// // Type inference lets us omit an explicit type signature (which | |
94b46f34 | 47 | /// // would be `HashSet<String>` in this example). |
1a4d82fc JJ |
48 | /// let mut books = HashSet::new(); |
49 | /// | |
50 | /// // Add some books. | |
94b46f34 XL |
51 | /// books.insert("A Dance With Dragons".to_string()); |
52 | /// books.insert("To Kill a Mockingbird".to_string()); | |
53 | /// books.insert("The Odyssey".to_string()); | |
54 | /// books.insert("The Great Gatsby".to_string()); | |
1a4d82fc JJ |
55 | /// |
56 | /// // Check for a specific one. | |
d9579d0f | 57 | /// if !books.contains("The Winds of Winter") { |
1a4d82fc JJ |
58 | /// println!("We have {} books, but The Winds of Winter ain't one.", |
59 | /// books.len()); | |
60 | /// } | |
61 | /// | |
62 | /// // Remove a book. | |
d9579d0f | 63 | /// books.remove("The Odyssey"); |
1a4d82fc JJ |
64 | /// |
65 | /// // Iterate over everything. | |
d9579d0f AL |
66 | /// for book in &books { |
67 | /// println!("{}", book); | |
1a4d82fc JJ |
68 | /// } |
69 | /// ``` | |
70 | /// | |
71 | /// The easiest way to use `HashSet` with a custom type is to derive | |
cc61c64b XL |
72 | /// [`Eq`] and [`Hash`]. We must also derive [`PartialEq`], this will in the |
73 | /// future be implied by [`Eq`]. | |
1a4d82fc JJ |
74 | /// |
75 | /// ``` | |
76 | /// use std::collections::HashSet; | |
85aaf69f | 77 | /// #[derive(Hash, Eq, PartialEq, Debug)] |
94b46f34 XL |
78 | /// struct Viking { |
79 | /// name: String, | |
85aaf69f | 80 | /// power: usize, |
1a4d82fc JJ |
81 | /// } |
82 | /// | |
83 | /// let mut vikings = HashSet::new(); | |
84 | /// | |
94b46f34 XL |
85 | /// vikings.insert(Viking { name: "Einar".to_string(), power: 9 }); |
86 | /// vikings.insert(Viking { name: "Einar".to_string(), power: 9 }); | |
87 | /// vikings.insert(Viking { name: "Olaf".to_string(), power: 4 }); | |
88 | /// vikings.insert(Viking { name: "Harald".to_string(), power: 8 }); | |
1a4d82fc JJ |
89 | /// |
90 | /// // Use derived implementation to print the vikings. | |
d9579d0f | 91 | /// for x in &vikings { |
1a4d82fc JJ |
92 | /// println!("{:?}", x); |
93 | /// } | |
94 | /// ``` | |
c30ab7b3 | 95 | /// |
cc61c64b | 96 | /// A `HashSet` with fixed list of elements can be initialized from an array: |
c30ab7b3 SL |
97 | /// |
98 | /// ``` | |
99 | /// use std::collections::HashSet; | |
100 | /// | |
e74abb32 XL |
101 | /// let viking_names: HashSet<&'static str> = |
102 | /// [ "Einar", "Olaf", "Harald" ].iter().cloned().collect(); | |
103 | /// // use the values stored in the set | |
c30ab7b3 | 104 | /// ``` |
cc61c64b | 105 | /// |
1b1a35ee | 106 | /// [`HashMap`]: crate::collections::HashMap |
3dfed10e XL |
107 | /// [`RefCell`]: crate::cell::RefCell |
108 | /// [`Cell`]: crate::cell::Cell | |
1a4d82fc | 109 | #[derive(Clone)] |
f9f354fc | 110 | #[cfg_attr(not(test), rustc_diagnostic_item = "hashset_type")] |
85aaf69f | 111 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 112 | pub struct HashSet<T, S = RandomState> { |
1b1a35ee | 113 | base: base::HashSet<T, S>, |
1a4d82fc JJ |
114 | } |
115 | ||
74b04a01 | 116 | impl<T> HashSet<T, RandomState> { |
3b2f2976 | 117 | /// Creates an empty `HashSet`. |
1a4d82fc | 118 | /// |
ea8adc8c XL |
119 | /// The hash set is initially created with a capacity of 0, so it will not allocate until it |
120 | /// is first inserted into. | |
121 | /// | |
c34b1796 | 122 | /// # Examples |
1a4d82fc JJ |
123 | /// |
124 | /// ``` | |
125 | /// use std::collections::HashSet; | |
3b2f2976 | 126 | /// let set: HashSet<i32> = HashSet::new(); |
1a4d82fc JJ |
127 | /// ``` |
128 | #[inline] | |
85aaf69f | 129 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 130 | pub fn new() -> HashSet<T, RandomState> { |
1b1a35ee | 131 | Default::default() |
1a4d82fc JJ |
132 | } |
133 | ||
c30ab7b3 SL |
134 | /// Creates an empty `HashSet` with the specified capacity. |
135 | /// | |
136 | /// The hash set will be able to hold at least `capacity` elements without | |
137 | /// reallocating. If `capacity` is 0, the hash set will not allocate. | |
1a4d82fc | 138 | /// |
c34b1796 | 139 | /// # Examples |
1a4d82fc JJ |
140 | /// |
141 | /// ``` | |
142 | /// use std::collections::HashSet; | |
3b2f2976 XL |
143 | /// let set: HashSet<i32> = HashSet::with_capacity(10); |
144 | /// assert!(set.capacity() >= 10); | |
1a4d82fc JJ |
145 | /// ``` |
146 | #[inline] | |
85aaf69f SL |
147 | #[stable(feature = "rust1", since = "1.0.0")] |
148 | pub fn with_capacity(capacity: usize) -> HashSet<T, RandomState> { | |
1b1a35ee | 149 | HashSet { base: base::HashSet::with_capacity_and_hasher(capacity, Default::default()) } |
1a4d82fc JJ |
150 | } |
151 | } | |
152 | ||
9fa01778 XL |
153 | impl<T, S> HashSet<T, S> { |
154 | /// Returns the number of elements the set can hold without reallocating. | |
155 | /// | |
156 | /// # Examples | |
157 | /// | |
158 | /// ``` | |
159 | /// use std::collections::HashSet; | |
160 | /// let set: HashSet<i32> = HashSet::with_capacity(100); | |
161 | /// assert!(set.capacity() >= 100); | |
162 | /// ``` | |
163 | #[inline] | |
164 | #[stable(feature = "rust1", since = "1.0.0")] | |
165 | pub fn capacity(&self) -> usize { | |
1b1a35ee | 166 | self.base.capacity() |
9fa01778 XL |
167 | } |
168 | ||
169 | /// An iterator visiting all elements in arbitrary order. | |
170 | /// The iterator element type is `&'a T`. | |
171 | /// | |
172 | /// # Examples | |
173 | /// | |
174 | /// ``` | |
175 | /// use std::collections::HashSet; | |
176 | /// let mut set = HashSet::new(); | |
177 | /// set.insert("a"); | |
178 | /// set.insert("b"); | |
179 | /// | |
180 | /// // Will print in an arbitrary order. | |
181 | /// for x in set.iter() { | |
182 | /// println!("{}", x); | |
183 | /// } | |
184 | /// ``` | |
48663c56 | 185 | #[inline] |
9fa01778 | 186 | #[stable(feature = "rust1", since = "1.0.0")] |
532ac7d7 | 187 | pub fn iter(&self) -> Iter<'_, T> { |
1b1a35ee | 188 | Iter { base: self.base.iter() } |
9fa01778 XL |
189 | } |
190 | ||
191 | /// Returns the number of elements in the set. | |
192 | /// | |
193 | /// # Examples | |
194 | /// | |
195 | /// ``` | |
196 | /// use std::collections::HashSet; | |
197 | /// | |
198 | /// let mut v = HashSet::new(); | |
199 | /// assert_eq!(v.len(), 0); | |
200 | /// v.insert(1); | |
201 | /// assert_eq!(v.len(), 1); | |
202 | /// ``` | |
48663c56 | 203 | #[inline] |
9fa01778 XL |
204 | #[stable(feature = "rust1", since = "1.0.0")] |
205 | pub fn len(&self) -> usize { | |
1b1a35ee | 206 | self.base.len() |
9fa01778 XL |
207 | } |
208 | ||
209 | /// Returns `true` if the set contains no elements. | |
210 | /// | |
211 | /// # Examples | |
212 | /// | |
213 | /// ``` | |
214 | /// use std::collections::HashSet; | |
215 | /// | |
216 | /// let mut v = HashSet::new(); | |
217 | /// assert!(v.is_empty()); | |
218 | /// v.insert(1); | |
219 | /// assert!(!v.is_empty()); | |
220 | /// ``` | |
48663c56 | 221 | #[inline] |
9fa01778 XL |
222 | #[stable(feature = "rust1", since = "1.0.0")] |
223 | pub fn is_empty(&self) -> bool { | |
1b1a35ee | 224 | self.base.is_empty() |
9fa01778 XL |
225 | } |
226 | ||
227 | /// Clears the set, returning all elements in an iterator. | |
228 | /// | |
229 | /// # Examples | |
230 | /// | |
231 | /// ``` | |
232 | /// use std::collections::HashSet; | |
233 | /// | |
234 | /// let mut set: HashSet<_> = [1, 2, 3].iter().cloned().collect(); | |
235 | /// assert!(!set.is_empty()); | |
236 | /// | |
237 | /// // print 1, 2, 3 in an arbitrary order | |
238 | /// for i in set.drain() { | |
239 | /// println!("{}", i); | |
240 | /// } | |
241 | /// | |
242 | /// assert!(set.is_empty()); | |
243 | /// ``` | |
244 | #[inline] | |
245 | #[stable(feature = "drain", since = "1.6.0")] | |
532ac7d7 | 246 | pub fn drain(&mut self) -> Drain<'_, T> { |
1b1a35ee XL |
247 | Drain { base: self.base.drain() } |
248 | } | |
249 | ||
250 | /// Creates an iterator which uses a closure to determine if a value should be removed. | |
251 | /// | |
252 | /// If the closure returns true, then the value is removed and yielded. | |
253 | /// If the closure returns false, the value will remain in the list and will not be yielded | |
254 | /// by the iterator. | |
255 | /// | |
256 | /// If the iterator is only partially consumed or not consumed at all, each of the remaining | |
257 | /// values will still be subjected to the closure and removed and dropped if it returns true. | |
258 | /// | |
259 | /// It is unspecified how many more values will be subjected to the closure | |
260 | /// if a panic occurs in the closure, or if a panic occurs while dropping a value, or if the | |
261 | /// `DrainFilter` itself is leaked. | |
262 | /// | |
263 | /// # Examples | |
264 | /// | |
265 | /// Splitting a set into even and odd values, reusing the original set: | |
266 | /// | |
267 | /// ``` | |
268 | /// #![feature(hash_drain_filter)] | |
269 | /// use std::collections::HashSet; | |
270 | /// | |
271 | /// let mut set: HashSet<i32> = (0..8).collect(); | |
272 | /// let drained: HashSet<i32> = set.drain_filter(|v| v % 2 == 0).collect(); | |
273 | /// | |
274 | /// let mut evens = drained.into_iter().collect::<Vec<_>>(); | |
275 | /// let mut odds = set.into_iter().collect::<Vec<_>>(); | |
276 | /// evens.sort(); | |
277 | /// odds.sort(); | |
278 | /// | |
279 | /// assert_eq!(evens, vec![0, 2, 4, 6]); | |
280 | /// assert_eq!(odds, vec![1, 3, 5, 7]); | |
281 | /// ``` | |
282 | #[inline] | |
283 | #[unstable(feature = "hash_drain_filter", issue = "59618")] | |
284 | pub fn drain_filter<F>(&mut self, pred: F) -> DrainFilter<'_, T, F> | |
285 | where | |
286 | F: FnMut(&T) -> bool, | |
287 | { | |
288 | DrainFilter { base: self.base.drain_filter(pred) } | |
9fa01778 XL |
289 | } |
290 | ||
291 | /// Clears the set, removing all values. | |
292 | /// | |
293 | /// # Examples | |
294 | /// | |
295 | /// ``` | |
296 | /// use std::collections::HashSet; | |
297 | /// | |
298 | /// let mut v = HashSet::new(); | |
299 | /// v.insert(1); | |
300 | /// v.clear(); | |
301 | /// assert!(v.is_empty()); | |
302 | /// ``` | |
48663c56 | 303 | #[inline] |
9fa01778 XL |
304 | #[stable(feature = "rust1", since = "1.0.0")] |
305 | pub fn clear(&mut self) { | |
1b1a35ee | 306 | self.base.clear() |
9fa01778 | 307 | } |
9fa01778 | 308 | |
1a4d82fc JJ |
309 | /// Creates a new empty hash set which will use the given hasher to hash |
310 | /// keys. | |
311 | /// | |
312 | /// The hash set is also created with the default initial capacity. | |
313 | /// | |
9cc50fc6 SL |
314 | /// Warning: `hasher` is normally randomly generated, and |
315 | /// is designed to allow `HashSet`s to be resistant to attacks that | |
316 | /// cause many collisions and very poor performance. Setting it | |
317 | /// manually using this function can expose a DoS attack vector. | |
318 | /// | |
f9f354fc XL |
319 | /// The `hash_builder` passed should implement the [`BuildHasher`] trait for |
320 | /// the HashMap to be useful, see its documentation for details. | |
321 | /// | |
c34b1796 | 322 | /// # Examples |
1a4d82fc JJ |
323 | /// |
324 | /// ``` | |
325 | /// use std::collections::HashSet; | |
326 | /// use std::collections::hash_map::RandomState; | |
327 | /// | |
328 | /// let s = RandomState::new(); | |
9cc50fc6 | 329 | /// let mut set = HashSet::with_hasher(s); |
85aaf69f | 330 | /// set.insert(2); |
1a4d82fc JJ |
331 | /// ``` |
332 | #[inline] | |
9cc50fc6 SL |
333 | #[stable(feature = "hashmap_build_hasher", since = "1.7.0")] |
334 | pub fn with_hasher(hasher: S) -> HashSet<T, S> { | |
1b1a35ee | 335 | HashSet { base: base::HashSet::with_hasher(hasher) } |
1a4d82fc JJ |
336 | } |
337 | ||
0731742a | 338 | /// Creates an empty `HashSet` with the specified capacity, using |
c30ab7b3 SL |
339 | /// `hasher` to hash the keys. |
340 | /// | |
341 | /// The hash set will be able to hold at least `capacity` elements without | |
342 | /// reallocating. If `capacity` is 0, the hash set will not allocate. | |
1a4d82fc JJ |
343 | /// |
344 | /// Warning: `hasher` is normally randomly generated, and | |
345 | /// is designed to allow `HashSet`s to be resistant to attacks that | |
346 | /// cause many collisions and very poor performance. Setting it | |
347 | /// manually using this function can expose a DoS attack vector. | |
348 | /// | |
f9f354fc XL |
349 | /// The `hash_builder` passed should implement the [`BuildHasher`] trait for |
350 | /// the HashMap to be useful, see its documentation for details. | |
351 | /// | |
c34b1796 | 352 | /// # Examples |
1a4d82fc JJ |
353 | /// |
354 | /// ``` | |
355 | /// use std::collections::HashSet; | |
356 | /// use std::collections::hash_map::RandomState; | |
357 | /// | |
358 | /// let s = RandomState::new(); | |
9cc50fc6 | 359 | /// let mut set = HashSet::with_capacity_and_hasher(10, s); |
85aaf69f | 360 | /// set.insert(1); |
1a4d82fc JJ |
361 | /// ``` |
362 | #[inline] | |
9cc50fc6 | 363 | #[stable(feature = "hashmap_build_hasher", since = "1.7.0")] |
c30ab7b3 | 364 | pub fn with_capacity_and_hasher(capacity: usize, hasher: S) -> HashSet<T, S> { |
1b1a35ee | 365 | HashSet { base: base::HashSet::with_capacity_and_hasher(capacity, hasher) } |
9cc50fc6 SL |
366 | } |
367 | ||
cc61c64b XL |
368 | /// Returns a reference to the set's [`BuildHasher`]. |
369 | /// | |
3b2f2976 XL |
370 | /// # Examples |
371 | /// | |
372 | /// ``` | |
373 | /// use std::collections::HashSet; | |
374 | /// use std::collections::hash_map::RandomState; | |
375 | /// | |
376 | /// let hasher = RandomState::new(); | |
377 | /// let set: HashSet<i32> = HashSet::with_hasher(hasher); | |
378 | /// let hasher: &RandomState = set.hasher(); | |
379 | /// ``` | |
48663c56 | 380 | #[inline] |
54a0048b | 381 | #[stable(feature = "hashmap_public_hasher", since = "1.9.0")] |
7453a54e | 382 | pub fn hasher(&self) -> &S { |
1b1a35ee | 383 | self.base.hasher() |
7453a54e | 384 | } |
74b04a01 | 385 | } |
7453a54e | 386 | |
74b04a01 XL |
387 | impl<T, S> HashSet<T, S> |
388 | where | |
389 | T: Eq + Hash, | |
390 | S: BuildHasher, | |
391 | { | |
1a4d82fc JJ |
392 | /// Reserves capacity for at least `additional` more elements to be inserted |
393 | /// in the `HashSet`. The collection may reserve more space to avoid | |
394 | /// frequent reallocations. | |
395 | /// | |
396 | /// # Panics | |
397 | /// | |
85aaf69f | 398 | /// Panics if the new allocation size overflows `usize`. |
1a4d82fc | 399 | /// |
c34b1796 | 400 | /// # Examples |
1a4d82fc JJ |
401 | /// |
402 | /// ``` | |
403 | /// use std::collections::HashSet; | |
85aaf69f | 404 | /// let mut set: HashSet<i32> = HashSet::new(); |
1a4d82fc | 405 | /// set.reserve(10); |
3b2f2976 | 406 | /// assert!(set.capacity() >= 10); |
1a4d82fc | 407 | /// ``` |
48663c56 | 408 | #[inline] |
85aaf69f SL |
409 | #[stable(feature = "rust1", since = "1.0.0")] |
410 | pub fn reserve(&mut self, additional: usize) { | |
1b1a35ee | 411 | self.base.reserve(additional) |
1a4d82fc JJ |
412 | } |
413 | ||
48663c56 XL |
414 | /// Tries to reserve capacity for at least `additional` more elements to be inserted |
415 | /// in the given `HashSet<K,V>`. The collection may reserve more space to avoid | |
416 | /// frequent reallocations. | |
417 | /// | |
418 | /// # Errors | |
419 | /// | |
420 | /// If the capacity overflows, or the allocator reports a failure, then an error | |
421 | /// is returned. | |
422 | /// | |
423 | /// # Examples | |
424 | /// | |
425 | /// ``` | |
426 | /// #![feature(try_reserve)] | |
427 | /// use std::collections::HashSet; | |
428 | /// let mut set: HashSet<i32> = HashSet::new(); | |
429 | /// set.try_reserve(10).expect("why is the test harness OOMing on 10 bytes?"); | |
430 | /// ``` | |
431 | #[inline] | |
dfeec247 | 432 | #[unstable(feature = "try_reserve", reason = "new API", issue = "48043")] |
e1599b0c | 433 | pub fn try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError> { |
1b1a35ee | 434 | self.base.try_reserve(additional).map_err(map_try_reserve_error) |
48663c56 XL |
435 | } |
436 | ||
1a4d82fc JJ |
437 | /// Shrinks the capacity of the set as much as possible. It will drop |
438 | /// down as much as possible while maintaining the internal rules | |
439 | /// and possibly leaving some space in accordance with the resize policy. | |
440 | /// | |
c34b1796 | 441 | /// # Examples |
1a4d82fc JJ |
442 | /// |
443 | /// ``` | |
444 | /// use std::collections::HashSet; | |
445 | /// | |
85aaf69f | 446 | /// let mut set = HashSet::with_capacity(100); |
1a4d82fc JJ |
447 | /// set.insert(1); |
448 | /// set.insert(2); | |
449 | /// assert!(set.capacity() >= 100); | |
450 | /// set.shrink_to_fit(); | |
451 | /// assert!(set.capacity() >= 2); | |
452 | /// ``` | |
48663c56 | 453 | #[inline] |
85aaf69f | 454 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 455 | pub fn shrink_to_fit(&mut self) { |
1b1a35ee | 456 | self.base.shrink_to_fit() |
1a4d82fc JJ |
457 | } |
458 | ||
0531ce1d XL |
459 | /// Shrinks the capacity of the set with a lower limit. It will drop |
460 | /// down no lower than the supplied limit while maintaining the internal rules | |
461 | /// and possibly leaving some space in accordance with the resize policy. | |
462 | /// | |
463 | /// Panics if the current capacity is smaller than the supplied | |
464 | /// minimum capacity. | |
465 | /// | |
466 | /// # Examples | |
467 | /// | |
468 | /// ``` | |
469 | /// #![feature(shrink_to)] | |
470 | /// use std::collections::HashSet; | |
471 | /// | |
472 | /// let mut set = HashSet::with_capacity(100); | |
473 | /// set.insert(1); | |
474 | /// set.insert(2); | |
475 | /// assert!(set.capacity() >= 100); | |
476 | /// set.shrink_to(10); | |
477 | /// assert!(set.capacity() >= 10); | |
478 | /// set.shrink_to(0); | |
479 | /// assert!(set.capacity() >= 2); | |
480 | /// ``` | |
481 | #[inline] | |
dfeec247 | 482 | #[unstable(feature = "shrink_to", reason = "new API", issue = "56431")] |
0531ce1d | 483 | pub fn shrink_to(&mut self, min_capacity: usize) { |
1b1a35ee | 484 | self.base.shrink_to(min_capacity) |
0531ce1d XL |
485 | } |
486 | ||
cc61c64b | 487 | /// Visits the values representing the difference, |
0731742a | 488 | /// i.e., the values that are in `self` but not in `other`. |
1a4d82fc | 489 | /// |
c34b1796 | 490 | /// # Examples |
1a4d82fc JJ |
491 | /// |
492 | /// ``` | |
493 | /// use std::collections::HashSet; | |
85aaf69f SL |
494 | /// let a: HashSet<_> = [1, 2, 3].iter().cloned().collect(); |
495 | /// let b: HashSet<_> = [4, 2, 3, 4].iter().cloned().collect(); | |
1a4d82fc JJ |
496 | /// |
497 | /// // Can be seen as `a - b`. | |
498 | /// for x in a.difference(&b) { | |
499 | /// println!("{}", x); // Print 1 | |
500 | /// } | |
501 | /// | |
3b2f2976 XL |
502 | /// let diff: HashSet<_> = a.difference(&b).collect(); |
503 | /// assert_eq!(diff, [1].iter().collect()); | |
1a4d82fc JJ |
504 | /// |
505 | /// // Note that difference is not symmetric, | |
506 | /// // and `b - a` means something else: | |
3b2f2976 XL |
507 | /// let diff: HashSet<_> = b.difference(&a).collect(); |
508 | /// assert_eq!(diff, [4].iter().collect()); | |
1a4d82fc | 509 | /// ``` |
48663c56 | 510 | #[inline] |
85aaf69f | 511 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 512 | pub fn difference<'a>(&'a self, other: &'a HashSet<T, S>) -> Difference<'a, T, S> { |
dfeec247 | 513 | Difference { iter: self.iter(), other } |
1a4d82fc JJ |
514 | } |
515 | ||
cc61c64b | 516 | /// Visits the values representing the symmetric difference, |
0731742a | 517 | /// i.e., the values that are in `self` or in `other` but not in both. |
1a4d82fc | 518 | /// |
c34b1796 | 519 | /// # Examples |
1a4d82fc JJ |
520 | /// |
521 | /// ``` | |
522 | /// use std::collections::HashSet; | |
85aaf69f SL |
523 | /// let a: HashSet<_> = [1, 2, 3].iter().cloned().collect(); |
524 | /// let b: HashSet<_> = [4, 2, 3, 4].iter().cloned().collect(); | |
1a4d82fc JJ |
525 | /// |
526 | /// // Print 1, 4 in arbitrary order. | |
527 | /// for x in a.symmetric_difference(&b) { | |
528 | /// println!("{}", x); | |
529 | /// } | |
530 | /// | |
3b2f2976 XL |
531 | /// let diff1: HashSet<_> = a.symmetric_difference(&b).collect(); |
532 | /// let diff2: HashSet<_> = b.symmetric_difference(&a).collect(); | |
1a4d82fc JJ |
533 | /// |
534 | /// assert_eq!(diff1, diff2); | |
3b2f2976 | 535 | /// assert_eq!(diff1, [1, 4].iter().collect()); |
1a4d82fc | 536 | /// ``` |
48663c56 | 537 | #[inline] |
85aaf69f | 538 | #[stable(feature = "rust1", since = "1.0.0")] |
dfeec247 XL |
539 | pub fn symmetric_difference<'a>( |
540 | &'a self, | |
541 | other: &'a HashSet<T, S>, | |
542 | ) -> SymmetricDifference<'a, T, S> { | |
1a4d82fc JJ |
543 | SymmetricDifference { iter: self.difference(other).chain(other.difference(self)) } |
544 | } | |
545 | ||
cc61c64b | 546 | /// Visits the values representing the intersection, |
0731742a | 547 | /// i.e., the values that are both in `self` and `other`. |
1a4d82fc | 548 | /// |
c34b1796 | 549 | /// # Examples |
1a4d82fc JJ |
550 | /// |
551 | /// ``` | |
552 | /// use std::collections::HashSet; | |
85aaf69f SL |
553 | /// let a: HashSet<_> = [1, 2, 3].iter().cloned().collect(); |
554 | /// let b: HashSet<_> = [4, 2, 3, 4].iter().cloned().collect(); | |
1a4d82fc JJ |
555 | /// |
556 | /// // Print 2, 3 in arbitrary order. | |
557 | /// for x in a.intersection(&b) { | |
558 | /// println!("{}", x); | |
559 | /// } | |
560 | /// | |
3b2f2976 XL |
561 | /// let intersection: HashSet<_> = a.intersection(&b).collect(); |
562 | /// assert_eq!(intersection, [2, 3].iter().collect()); | |
1a4d82fc | 563 | /// ``` |
48663c56 | 564 | #[inline] |
85aaf69f | 565 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 566 | pub fn intersection<'a>(&'a self, other: &'a HashSet<T, S>) -> Intersection<'a, T, S> { |
0731742a | 567 | if self.len() <= other.len() { |
dfeec247 | 568 | Intersection { iter: self.iter(), other } |
0731742a | 569 | } else { |
dfeec247 | 570 | Intersection { iter: other.iter(), other: self } |
1a4d82fc JJ |
571 | } |
572 | } | |
573 | ||
cc61c64b | 574 | /// Visits the values representing the union, |
0731742a | 575 | /// i.e., all the values in `self` or `other`, without duplicates. |
1a4d82fc | 576 | /// |
c34b1796 | 577 | /// # Examples |
1a4d82fc JJ |
578 | /// |
579 | /// ``` | |
580 | /// use std::collections::HashSet; | |
85aaf69f SL |
581 | /// let a: HashSet<_> = [1, 2, 3].iter().cloned().collect(); |
582 | /// let b: HashSet<_> = [4, 2, 3, 4].iter().cloned().collect(); | |
1a4d82fc JJ |
583 | /// |
584 | /// // Print 1, 2, 3, 4 in arbitrary order. | |
585 | /// for x in a.union(&b) { | |
586 | /// println!("{}", x); | |
587 | /// } | |
588 | /// | |
3b2f2976 XL |
589 | /// let union: HashSet<_> = a.union(&b).collect(); |
590 | /// assert_eq!(union, [1, 2, 3, 4].iter().collect()); | |
1a4d82fc | 591 | /// ``` |
48663c56 | 592 | #[inline] |
85aaf69f | 593 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 594 | pub fn union<'a>(&'a self, other: &'a HashSet<T, S>) -> Union<'a, T, S> { |
60c5eb7d | 595 | if self.len() >= other.len() { |
dfeec247 | 596 | Union { iter: self.iter().chain(other.difference(self)) } |
0731742a | 597 | } else { |
dfeec247 | 598 | Union { iter: other.iter().chain(self.difference(other)) } |
0731742a | 599 | } |
1a4d82fc JJ |
600 | } |
601 | ||
1a4d82fc JJ |
602 | /// Returns `true` if the set contains a value. |
603 | /// | |
604 | /// The value may be any borrowed form of the set's value type, but | |
cc61c64b | 605 | /// [`Hash`] and [`Eq`] on the borrowed form *must* match those for |
1a4d82fc JJ |
606 | /// the value type. |
607 | /// | |
c34b1796 | 608 | /// # Examples |
1a4d82fc JJ |
609 | /// |
610 | /// ``` | |
611 | /// use std::collections::HashSet; | |
612 | /// | |
85aaf69f | 613 | /// let set: HashSet<_> = [1, 2, 3].iter().cloned().collect(); |
1a4d82fc JJ |
614 | /// assert_eq!(set.contains(&1), true); |
615 | /// assert_eq!(set.contains(&4), false); | |
616 | /// ``` | |
48663c56 | 617 | #[inline] |
85aaf69f | 618 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 619 | pub fn contains<Q: ?Sized>(&self, value: &Q) -> bool |
dfeec247 XL |
620 | where |
621 | T: Borrow<Q>, | |
622 | Q: Hash + Eq, | |
1a4d82fc | 623 | { |
1b1a35ee | 624 | self.base.contains(value) |
1a4d82fc JJ |
625 | } |
626 | ||
e9174d1e SL |
627 | /// Returns a reference to the value in the set, if any, that is equal to the given value. |
628 | /// | |
629 | /// The value may be any borrowed form of the set's value type, but | |
cc61c64b | 630 | /// [`Hash`] and [`Eq`] on the borrowed form *must* match those for |
e9174d1e | 631 | /// the value type. |
cc61c64b | 632 | /// |
2c00a5a8 XL |
633 | /// # Examples |
634 | /// | |
635 | /// ``` | |
636 | /// use std::collections::HashSet; | |
637 | /// | |
638 | /// let set: HashSet<_> = [1, 2, 3].iter().cloned().collect(); | |
639 | /// assert_eq!(set.get(&2), Some(&2)); | |
640 | /// assert_eq!(set.get(&4), None); | |
641 | /// ``` | |
48663c56 | 642 | #[inline] |
54a0048b | 643 | #[stable(feature = "set_recovery", since = "1.9.0")] |
e9174d1e | 644 | pub fn get<Q: ?Sized>(&self, value: &Q) -> Option<&T> |
dfeec247 XL |
645 | where |
646 | T: Borrow<Q>, | |
647 | Q: Hash + Eq, | |
e9174d1e | 648 | { |
1b1a35ee | 649 | self.base.get(value) |
48663c56 XL |
650 | } |
651 | ||
652 | /// Inserts the given `value` into the set if it is not present, then | |
653 | /// returns a reference to the value in the set. | |
654 | /// | |
655 | /// # Examples | |
656 | /// | |
657 | /// ``` | |
658 | /// #![feature(hash_set_entry)] | |
659 | /// | |
660 | /// use std::collections::HashSet; | |
661 | /// | |
662 | /// let mut set: HashSet<_> = [1, 2, 3].iter().cloned().collect(); | |
663 | /// assert_eq!(set.len(), 3); | |
664 | /// assert_eq!(set.get_or_insert(2), &2); | |
665 | /// assert_eq!(set.get_or_insert(100), &100); | |
666 | /// assert_eq!(set.len(), 4); // 100 was inserted | |
667 | /// ``` | |
668 | #[inline] | |
669 | #[unstable(feature = "hash_set_entry", issue = "60896")] | |
670 | pub fn get_or_insert(&mut self, value: T) -> &T { | |
671 | // Although the raw entry gives us `&mut T`, we only return `&T` to be consistent with | |
672 | // `get`. Key mutation is "raw" because you're not supposed to affect `Eq` or `Hash`. | |
1b1a35ee | 673 | self.base.get_or_insert(value) |
48663c56 XL |
674 | } |
675 | ||
dfeec247 XL |
676 | /// Inserts an owned copy of the given `value` into the set if it is not |
677 | /// present, then returns a reference to the value in the set. | |
678 | /// | |
679 | /// # Examples | |
680 | /// | |
681 | /// ``` | |
682 | /// #![feature(hash_set_entry)] | |
683 | /// | |
684 | /// use std::collections::HashSet; | |
685 | /// | |
686 | /// let mut set: HashSet<String> = ["cat", "dog", "horse"] | |
687 | /// .iter().map(|&pet| pet.to_owned()).collect(); | |
688 | /// | |
689 | /// assert_eq!(set.len(), 3); | |
690 | /// for &pet in &["cat", "dog", "fish"] { | |
691 | /// let value = set.get_or_insert_owned(pet); | |
692 | /// assert_eq!(value, pet); | |
693 | /// } | |
694 | /// assert_eq!(set.len(), 4); // a new "fish" was inserted | |
695 | /// ``` | |
696 | #[inline] | |
697 | #[unstable(feature = "hash_set_entry", issue = "60896")] | |
698 | pub fn get_or_insert_owned<Q: ?Sized>(&mut self, value: &Q) -> &T | |
699 | where | |
700 | T: Borrow<Q>, | |
701 | Q: Hash + Eq + ToOwned<Owned = T>, | |
702 | { | |
703 | // Although the raw entry gives us `&mut T`, we only return `&T` to be consistent with | |
704 | // `get`. Key mutation is "raw" because you're not supposed to affect `Eq` or `Hash`. | |
1b1a35ee | 705 | self.base.get_or_insert_owned(value) |
dfeec247 XL |
706 | } |
707 | ||
48663c56 XL |
708 | /// Inserts a value computed from `f` into the set if the given `value` is |
709 | /// not present, then returns a reference to the value in the set. | |
710 | /// | |
711 | /// # Examples | |
712 | /// | |
713 | /// ``` | |
714 | /// #![feature(hash_set_entry)] | |
715 | /// | |
716 | /// use std::collections::HashSet; | |
717 | /// | |
718 | /// let mut set: HashSet<String> = ["cat", "dog", "horse"] | |
719 | /// .iter().map(|&pet| pet.to_owned()).collect(); | |
720 | /// | |
721 | /// assert_eq!(set.len(), 3); | |
722 | /// for &pet in &["cat", "dog", "fish"] { | |
723 | /// let value = set.get_or_insert_with(pet, str::to_owned); | |
724 | /// assert_eq!(value, pet); | |
725 | /// } | |
726 | /// assert_eq!(set.len(), 4); // a new "fish" was inserted | |
727 | /// ``` | |
728 | #[inline] | |
729 | #[unstable(feature = "hash_set_entry", issue = "60896")] | |
730 | pub fn get_or_insert_with<Q: ?Sized, F>(&mut self, value: &Q, f: F) -> &T | |
dfeec247 XL |
731 | where |
732 | T: Borrow<Q>, | |
733 | Q: Hash + Eq, | |
734 | F: FnOnce(&Q) -> T, | |
48663c56 XL |
735 | { |
736 | // Although the raw entry gives us `&mut T`, we only return `&T` to be consistent with | |
737 | // `get`. Key mutation is "raw" because you're not supposed to affect `Eq` or `Hash`. | |
1b1a35ee | 738 | self.base.get_or_insert_with(value, f) |
e9174d1e SL |
739 | } |
740 | ||
8bb4bdeb | 741 | /// Returns `true` if `self` has no elements in common with `other`. |
1a4d82fc JJ |
742 | /// This is equivalent to checking for an empty intersection. |
743 | /// | |
c34b1796 | 744 | /// # Examples |
1a4d82fc JJ |
745 | /// |
746 | /// ``` | |
747 | /// use std::collections::HashSet; | |
748 | /// | |
85aaf69f SL |
749 | /// let a: HashSet<_> = [1, 2, 3].iter().cloned().collect(); |
750 | /// let mut b = HashSet::new(); | |
1a4d82fc JJ |
751 | /// |
752 | /// assert_eq!(a.is_disjoint(&b), true); | |
753 | /// b.insert(4); | |
754 | /// assert_eq!(a.is_disjoint(&b), true); | |
755 | /// b.insert(1); | |
756 | /// assert_eq!(a.is_disjoint(&b), false); | |
757 | /// ``` | |
85aaf69f | 758 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 759 | pub fn is_disjoint(&self, other: &HashSet<T, S>) -> bool { |
0731742a XL |
760 | if self.len() <= other.len() { |
761 | self.iter().all(|v| !other.contains(v)) | |
762 | } else { | |
763 | other.iter().all(|v| !self.contains(v)) | |
764 | } | |
1a4d82fc JJ |
765 | } |
766 | ||
8bb4bdeb | 767 | /// Returns `true` if the set is a subset of another, |
0731742a | 768 | /// i.e., `other` contains at least all the values in `self`. |
1a4d82fc | 769 | /// |
c34b1796 | 770 | /// # Examples |
1a4d82fc JJ |
771 | /// |
772 | /// ``` | |
773 | /// use std::collections::HashSet; | |
774 | /// | |
85aaf69f SL |
775 | /// let sup: HashSet<_> = [1, 2, 3].iter().cloned().collect(); |
776 | /// let mut set = HashSet::new(); | |
1a4d82fc JJ |
777 | /// |
778 | /// assert_eq!(set.is_subset(&sup), true); | |
779 | /// set.insert(2); | |
780 | /// assert_eq!(set.is_subset(&sup), true); | |
781 | /// set.insert(4); | |
782 | /// assert_eq!(set.is_subset(&sup), false); | |
783 | /// ``` | |
85aaf69f | 784 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 785 | pub fn is_subset(&self, other: &HashSet<T, S>) -> bool { |
dfeec247 | 786 | if self.len() <= other.len() { self.iter().all(|v| other.contains(v)) } else { false } |
1a4d82fc JJ |
787 | } |
788 | ||
8bb4bdeb | 789 | /// Returns `true` if the set is a superset of another, |
0731742a | 790 | /// i.e., `self` contains at least all the values in `other`. |
1a4d82fc | 791 | /// |
c34b1796 | 792 | /// # Examples |
1a4d82fc JJ |
793 | /// |
794 | /// ``` | |
795 | /// use std::collections::HashSet; | |
796 | /// | |
85aaf69f SL |
797 | /// let sub: HashSet<_> = [1, 2].iter().cloned().collect(); |
798 | /// let mut set = HashSet::new(); | |
1a4d82fc JJ |
799 | /// |
800 | /// assert_eq!(set.is_superset(&sub), false); | |
801 | /// | |
802 | /// set.insert(0); | |
803 | /// set.insert(1); | |
804 | /// assert_eq!(set.is_superset(&sub), false); | |
805 | /// | |
806 | /// set.insert(2); | |
807 | /// assert_eq!(set.is_superset(&sub), true); | |
808 | /// ``` | |
809 | #[inline] | |
85aaf69f | 810 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
811 | pub fn is_superset(&self, other: &HashSet<T, S>) -> bool { |
812 | other.is_subset(self) | |
813 | } | |
814 | ||
b039eaaf SL |
815 | /// Adds a value to the set. |
816 | /// | |
a7813a04 | 817 | /// If the set did not have this value present, `true` is returned. |
b039eaaf | 818 | /// |
a7813a04 | 819 | /// If the set did have this value present, `false` is returned. |
1a4d82fc | 820 | /// |
c34b1796 | 821 | /// # Examples |
1a4d82fc JJ |
822 | /// |
823 | /// ``` | |
824 | /// use std::collections::HashSet; | |
825 | /// | |
826 | /// let mut set = HashSet::new(); | |
827 | /// | |
85aaf69f | 828 | /// assert_eq!(set.insert(2), true); |
1a4d82fc JJ |
829 | /// assert_eq!(set.insert(2), false); |
830 | /// assert_eq!(set.len(), 1); | |
831 | /// ``` | |
48663c56 | 832 | #[inline] |
85aaf69f | 833 | #[stable(feature = "rust1", since = "1.0.0")] |
c30ab7b3 | 834 | pub fn insert(&mut self, value: T) -> bool { |
1b1a35ee | 835 | self.base.insert(value) |
c30ab7b3 | 836 | } |
1a4d82fc | 837 | |
e9174d1e SL |
838 | /// Adds a value to the set, replacing the existing value, if any, that is equal to the given |
839 | /// one. Returns the replaced value. | |
2c00a5a8 XL |
840 | /// |
841 | /// # Examples | |
842 | /// | |
843 | /// ``` | |
844 | /// use std::collections::HashSet; | |
845 | /// | |
846 | /// let mut set = HashSet::new(); | |
847 | /// set.insert(Vec::<i32>::new()); | |
848 | /// | |
849 | /// assert_eq!(set.get(&[][..]).unwrap().capacity(), 0); | |
850 | /// set.replace(Vec::with_capacity(10)); | |
851 | /// assert_eq!(set.get(&[][..]).unwrap().capacity(), 10); | |
852 | /// ``` | |
48663c56 | 853 | #[inline] |
54a0048b | 854 | #[stable(feature = "set_recovery", since = "1.9.0")] |
e9174d1e | 855 | pub fn replace(&mut self, value: T) -> Option<T> { |
1b1a35ee | 856 | self.base.replace(value) |
e9174d1e SL |
857 | } |
858 | ||
9fa01778 | 859 | /// Removes a value from the set. Returns whether the value was |
1a4d82fc JJ |
860 | /// present in the set. |
861 | /// | |
862 | /// The value may be any borrowed form of the set's value type, but | |
cc61c64b | 863 | /// [`Hash`] and [`Eq`] on the borrowed form *must* match those for |
1a4d82fc JJ |
864 | /// the value type. |
865 | /// | |
c34b1796 | 866 | /// # Examples |
1a4d82fc JJ |
867 | /// |
868 | /// ``` | |
869 | /// use std::collections::HashSet; | |
870 | /// | |
871 | /// let mut set = HashSet::new(); | |
872 | /// | |
85aaf69f | 873 | /// set.insert(2); |
1a4d82fc JJ |
874 | /// assert_eq!(set.remove(&2), true); |
875 | /// assert_eq!(set.remove(&2), false); | |
876 | /// ``` | |
48663c56 | 877 | #[inline] |
85aaf69f | 878 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 879 | pub fn remove<Q: ?Sized>(&mut self, value: &Q) -> bool |
dfeec247 XL |
880 | where |
881 | T: Borrow<Q>, | |
882 | Q: Hash + Eq, | |
1a4d82fc | 883 | { |
1b1a35ee | 884 | self.base.remove(value) |
1a4d82fc | 885 | } |
e9174d1e SL |
886 | |
887 | /// Removes and returns the value in the set, if any, that is equal to the given one. | |
888 | /// | |
889 | /// The value may be any borrowed form of the set's value type, but | |
cc61c64b | 890 | /// [`Hash`] and [`Eq`] on the borrowed form *must* match those for |
e9174d1e | 891 | /// the value type. |
cc61c64b | 892 | /// |
2c00a5a8 XL |
893 | /// # Examples |
894 | /// | |
895 | /// ``` | |
896 | /// use std::collections::HashSet; | |
897 | /// | |
898 | /// let mut set: HashSet<_> = [1, 2, 3].iter().cloned().collect(); | |
899 | /// assert_eq!(set.take(&2), Some(2)); | |
900 | /// assert_eq!(set.take(&2), None); | |
901 | /// ``` | |
48663c56 | 902 | #[inline] |
54a0048b | 903 | #[stable(feature = "set_recovery", since = "1.9.0")] |
e9174d1e | 904 | pub fn take<Q: ?Sized>(&mut self, value: &Q) -> Option<T> |
dfeec247 XL |
905 | where |
906 | T: Borrow<Q>, | |
907 | Q: Hash + Eq, | |
e9174d1e | 908 | { |
1b1a35ee | 909 | self.base.take(value) |
e9174d1e | 910 | } |
8bb4bdeb XL |
911 | |
912 | /// Retains only the elements specified by the predicate. | |
913 | /// | |
914 | /// In other words, remove all elements `e` such that `f(&e)` returns `false`. | |
915 | /// | |
916 | /// # Examples | |
917 | /// | |
918 | /// ``` | |
8bb4bdeb XL |
919 | /// use std::collections::HashSet; |
920 | /// | |
921 | /// let xs = [1,2,3,4,5,6]; | |
0531ce1d | 922 | /// let mut set: HashSet<i32> = xs.iter().cloned().collect(); |
8bb4bdeb XL |
923 | /// set.retain(|&k| k % 2 == 0); |
924 | /// assert_eq!(set.len(), 3); | |
925 | /// ``` | |
cc61c64b | 926 | #[stable(feature = "retain_hash_collection", since = "1.18.0")] |
1b1a35ee | 927 | pub fn retain<F>(&mut self, f: F) |
dfeec247 XL |
928 | where |
929 | F: FnMut(&T) -> bool, | |
8bb4bdeb | 930 | { |
1b1a35ee | 931 | self.base.retain(f) |
8bb4bdeb | 932 | } |
1a4d82fc JJ |
933 | } |
934 | ||
85aaf69f SL |
935 | #[stable(feature = "rust1", since = "1.0.0")] |
936 | impl<T, S> PartialEq for HashSet<T, S> | |
dfeec247 XL |
937 | where |
938 | T: Eq + Hash, | |
939 | S: BuildHasher, | |
1a4d82fc JJ |
940 | { |
941 | fn eq(&self, other: &HashSet<T, S>) -> bool { | |
c30ab7b3 SL |
942 | if self.len() != other.len() { |
943 | return false; | |
944 | } | |
1a4d82fc JJ |
945 | |
946 | self.iter().all(|key| other.contains(key)) | |
947 | } | |
948 | } | |
949 | ||
85aaf69f SL |
950 | #[stable(feature = "rust1", since = "1.0.0")] |
951 | impl<T, S> Eq for HashSet<T, S> | |
dfeec247 XL |
952 | where |
953 | T: Eq + Hash, | |
954 | S: BuildHasher, | |
c30ab7b3 SL |
955 | { |
956 | } | |
1a4d82fc | 957 | |
85aaf69f SL |
958 | #[stable(feature = "rust1", since = "1.0.0")] |
959 | impl<T, S> fmt::Debug for HashSet<T, S> | |
dfeec247 | 960 | where |
74b04a01 | 961 | T: fmt::Debug, |
1a4d82fc | 962 | { |
532ac7d7 | 963 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
62682a34 | 964 | f.debug_set().entries(self.iter()).finish() |
1a4d82fc JJ |
965 | } |
966 | } | |
967 | ||
85aaf69f SL |
968 | #[stable(feature = "rust1", since = "1.0.0")] |
969 | impl<T, S> FromIterator<T> for HashSet<T, S> | |
dfeec247 XL |
970 | where |
971 | T: Eq + Hash, | |
972 | S: BuildHasher + Default, | |
1a4d82fc | 973 | { |
48663c56 | 974 | #[inline] |
c30ab7b3 | 975 | fn from_iter<I: IntoIterator<Item = T>>(iter: I) -> HashSet<T, S> { |
476ff2be SL |
976 | let mut set = HashSet::with_hasher(Default::default()); |
977 | set.extend(iter); | |
1a4d82fc JJ |
978 | set |
979 | } | |
980 | } | |
981 | ||
85aaf69f SL |
982 | #[stable(feature = "rust1", since = "1.0.0")] |
983 | impl<T, S> Extend<T> for HashSet<T, S> | |
dfeec247 XL |
984 | where |
985 | T: Eq + Hash, | |
986 | S: BuildHasher, | |
1a4d82fc | 987 | { |
48663c56 | 988 | #[inline] |
c30ab7b3 | 989 | fn extend<I: IntoIterator<Item = T>>(&mut self, iter: I) { |
1b1a35ee | 990 | self.base.extend(iter); |
1a4d82fc | 991 | } |
f9f354fc XL |
992 | |
993 | #[inline] | |
994 | fn extend_one(&mut self, item: T) { | |
1b1a35ee | 995 | self.base.insert(item); |
f9f354fc XL |
996 | } |
997 | ||
998 | #[inline] | |
999 | fn extend_reserve(&mut self, additional: usize) { | |
1b1a35ee | 1000 | self.base.extend_reserve(additional); |
f9f354fc | 1001 | } |
1a4d82fc JJ |
1002 | } |
1003 | ||
e9174d1e SL |
1004 | #[stable(feature = "hash_extend_copy", since = "1.4.0")] |
1005 | impl<'a, T, S> Extend<&'a T> for HashSet<T, S> | |
dfeec247 XL |
1006 | where |
1007 | T: 'a + Eq + Hash + Copy, | |
1008 | S: BuildHasher, | |
e9174d1e | 1009 | { |
48663c56 | 1010 | #[inline] |
c30ab7b3 | 1011 | fn extend<I: IntoIterator<Item = &'a T>>(&mut self, iter: I) { |
e9174d1e SL |
1012 | self.extend(iter.into_iter().cloned()); |
1013 | } | |
f9f354fc XL |
1014 | |
1015 | #[inline] | |
1016 | fn extend_one(&mut self, &item: &'a T) { | |
1b1a35ee | 1017 | self.base.insert(item); |
f9f354fc XL |
1018 | } |
1019 | ||
1020 | #[inline] | |
1021 | fn extend_reserve(&mut self, additional: usize) { | |
1022 | Extend::<T>::extend_reserve(self, additional) | |
1023 | } | |
e9174d1e SL |
1024 | } |
1025 | ||
85aaf69f SL |
1026 | #[stable(feature = "rust1", since = "1.0.0")] |
1027 | impl<T, S> Default for HashSet<T, S> | |
dfeec247 | 1028 | where |
74b04a01 | 1029 | S: Default, |
1a4d82fc | 1030 | { |
9e0c209e | 1031 | /// Creates an empty `HashSet<T, S>` with the `Default` value for the hasher. |
48663c56 | 1032 | #[inline] |
1a4d82fc | 1033 | fn default() -> HashSet<T, S> { |
1b1a35ee | 1034 | HashSet { base: Default::default() } |
1a4d82fc JJ |
1035 | } |
1036 | } | |
1037 | ||
85aaf69f | 1038 | #[stable(feature = "rust1", since = "1.0.0")] |
532ac7d7 | 1039 | impl<T, S> BitOr<&HashSet<T, S>> for &HashSet<T, S> |
dfeec247 XL |
1040 | where |
1041 | T: Eq + Hash + Clone, | |
1042 | S: BuildHasher + Default, | |
1a4d82fc JJ |
1043 | { |
1044 | type Output = HashSet<T, S>; | |
1045 | ||
1046 | /// Returns the union of `self` and `rhs` as a new `HashSet<T, S>`. | |
1047 | /// | |
1048 | /// # Examples | |
1049 | /// | |
1050 | /// ``` | |
1051 | /// use std::collections::HashSet; | |
1052 | /// | |
85aaf69f SL |
1053 | /// let a: HashSet<_> = vec![1, 2, 3].into_iter().collect(); |
1054 | /// let b: HashSet<_> = vec![3, 4, 5].into_iter().collect(); | |
1a4d82fc | 1055 | /// |
85aaf69f | 1056 | /// let set = &a | &b; |
1a4d82fc JJ |
1057 | /// |
1058 | /// let mut i = 0; | |
1059 | /// let expected = [1, 2, 3, 4, 5]; | |
62682a34 | 1060 | /// for x in &set { |
1a4d82fc JJ |
1061 | /// assert!(expected.contains(x)); |
1062 | /// i += 1; | |
1063 | /// } | |
1064 | /// assert_eq!(i, expected.len()); | |
1065 | /// ``` | |
1066 | fn bitor(self, rhs: &HashSet<T, S>) -> HashSet<T, S> { | |
1067 | self.union(rhs).cloned().collect() | |
1068 | } | |
1069 | } | |
1070 | ||
85aaf69f | 1071 | #[stable(feature = "rust1", since = "1.0.0")] |
532ac7d7 | 1072 | impl<T, S> BitAnd<&HashSet<T, S>> for &HashSet<T, S> |
dfeec247 XL |
1073 | where |
1074 | T: Eq + Hash + Clone, | |
1075 | S: BuildHasher + Default, | |
1a4d82fc JJ |
1076 | { |
1077 | type Output = HashSet<T, S>; | |
1078 | ||
1079 | /// Returns the intersection of `self` and `rhs` as a new `HashSet<T, S>`. | |
1080 | /// | |
1081 | /// # Examples | |
1082 | /// | |
1083 | /// ``` | |
1084 | /// use std::collections::HashSet; | |
1085 | /// | |
85aaf69f SL |
1086 | /// let a: HashSet<_> = vec![1, 2, 3].into_iter().collect(); |
1087 | /// let b: HashSet<_> = vec![2, 3, 4].into_iter().collect(); | |
1a4d82fc | 1088 | /// |
85aaf69f | 1089 | /// let set = &a & &b; |
1a4d82fc JJ |
1090 | /// |
1091 | /// let mut i = 0; | |
1092 | /// let expected = [2, 3]; | |
62682a34 | 1093 | /// for x in &set { |
1a4d82fc JJ |
1094 | /// assert!(expected.contains(x)); |
1095 | /// i += 1; | |
1096 | /// } | |
1097 | /// assert_eq!(i, expected.len()); | |
1098 | /// ``` | |
1099 | fn bitand(self, rhs: &HashSet<T, S>) -> HashSet<T, S> { | |
1100 | self.intersection(rhs).cloned().collect() | |
1101 | } | |
1102 | } | |
1103 | ||
85aaf69f | 1104 | #[stable(feature = "rust1", since = "1.0.0")] |
532ac7d7 | 1105 | impl<T, S> BitXor<&HashSet<T, S>> for &HashSet<T, S> |
dfeec247 XL |
1106 | where |
1107 | T: Eq + Hash + Clone, | |
1108 | S: BuildHasher + Default, | |
1a4d82fc JJ |
1109 | { |
1110 | type Output = HashSet<T, S>; | |
1111 | ||
1112 | /// Returns the symmetric difference of `self` and `rhs` as a new `HashSet<T, S>`. | |
1113 | /// | |
1114 | /// # Examples | |
1115 | /// | |
1116 | /// ``` | |
1117 | /// use std::collections::HashSet; | |
1118 | /// | |
85aaf69f SL |
1119 | /// let a: HashSet<_> = vec![1, 2, 3].into_iter().collect(); |
1120 | /// let b: HashSet<_> = vec![3, 4, 5].into_iter().collect(); | |
1a4d82fc | 1121 | /// |
85aaf69f | 1122 | /// let set = &a ^ &b; |
1a4d82fc JJ |
1123 | /// |
1124 | /// let mut i = 0; | |
1125 | /// let expected = [1, 2, 4, 5]; | |
62682a34 | 1126 | /// for x in &set { |
1a4d82fc JJ |
1127 | /// assert!(expected.contains(x)); |
1128 | /// i += 1; | |
1129 | /// } | |
1130 | /// assert_eq!(i, expected.len()); | |
1131 | /// ``` | |
1132 | fn bitxor(self, rhs: &HashSet<T, S>) -> HashSet<T, S> { | |
1133 | self.symmetric_difference(rhs).cloned().collect() | |
1134 | } | |
1135 | } | |
1136 | ||
85aaf69f | 1137 | #[stable(feature = "rust1", since = "1.0.0")] |
532ac7d7 | 1138 | impl<T, S> Sub<&HashSet<T, S>> for &HashSet<T, S> |
dfeec247 XL |
1139 | where |
1140 | T: Eq + Hash + Clone, | |
1141 | S: BuildHasher + Default, | |
1a4d82fc JJ |
1142 | { |
1143 | type Output = HashSet<T, S>; | |
1144 | ||
1145 | /// Returns the difference of `self` and `rhs` as a new `HashSet<T, S>`. | |
1146 | /// | |
1147 | /// # Examples | |
1148 | /// | |
1149 | /// ``` | |
1150 | /// use std::collections::HashSet; | |
1151 | /// | |
85aaf69f SL |
1152 | /// let a: HashSet<_> = vec![1, 2, 3].into_iter().collect(); |
1153 | /// let b: HashSet<_> = vec![3, 4, 5].into_iter().collect(); | |
1a4d82fc | 1154 | /// |
85aaf69f | 1155 | /// let set = &a - &b; |
1a4d82fc JJ |
1156 | /// |
1157 | /// let mut i = 0; | |
1158 | /// let expected = [1, 2]; | |
62682a34 | 1159 | /// for x in &set { |
1a4d82fc JJ |
1160 | /// assert!(expected.contains(x)); |
1161 | /// i += 1; | |
1162 | /// } | |
1163 | /// assert_eq!(i, expected.len()); | |
1164 | /// ``` | |
1165 | fn sub(self, rhs: &HashSet<T, S>) -> HashSet<T, S> { | |
1166 | self.difference(rhs).cloned().collect() | |
1167 | } | |
1168 | } | |
1169 | ||
cc61c64b XL |
1170 | /// An iterator over the items of a `HashSet`. |
1171 | /// | |
1172 | /// This `struct` is created by the [`iter`] method on [`HashSet`]. | |
1173 | /// See its documentation for more. | |
1174 | /// | |
3dfed10e | 1175 | /// [`iter`]: HashSet::iter |
1b1a35ee XL |
1176 | /// |
1177 | /// # Examples | |
1178 | /// | |
1179 | /// ``` | |
1180 | /// use std::collections::HashSet; | |
1181 | /// | |
1182 | /// let a: HashSet<u32> = vec![1, 2, 3].into_iter().collect(); | |
1183 | /// | |
1184 | /// let mut iter = a.iter(); | |
1185 | /// ``` | |
85aaf69f | 1186 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 1187 | pub struct Iter<'a, K: 'a> { |
1b1a35ee | 1188 | base: base::Iter<'a, K>, |
1a4d82fc JJ |
1189 | } |
1190 | ||
cc61c64b XL |
1191 | /// An owning iterator over the items of a `HashSet`. |
1192 | /// | |
dfeec247 | 1193 | /// This `struct` is created by the [`into_iter`] method on [`HashSet`] |
cc61c64b XL |
1194 | /// (provided by the `IntoIterator` trait). See its documentation for more. |
1195 | /// | |
3dfed10e | 1196 | /// [`into_iter`]: IntoIterator::into_iter |
1b1a35ee XL |
1197 | /// |
1198 | /// # Examples | |
1199 | /// | |
1200 | /// ``` | |
1201 | /// use std::collections::HashSet; | |
1202 | /// | |
1203 | /// let a: HashSet<u32> = vec![1, 2, 3].into_iter().collect(); | |
1204 | /// | |
1205 | /// let mut iter = a.into_iter(); | |
1206 | /// ``` | |
85aaf69f | 1207 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 1208 | pub struct IntoIter<K> { |
1b1a35ee | 1209 | base: base::IntoIter<K>, |
1a4d82fc JJ |
1210 | } |
1211 | ||
cc61c64b XL |
1212 | /// A draining iterator over the items of a `HashSet`. |
1213 | /// | |
1214 | /// This `struct` is created by the [`drain`] method on [`HashSet`]. | |
1215 | /// See its documentation for more. | |
1216 | /// | |
3dfed10e | 1217 | /// [`drain`]: HashSet::drain |
1b1a35ee XL |
1218 | /// |
1219 | /// # Examples | |
1220 | /// | |
1221 | /// ``` | |
1222 | /// use std::collections::HashSet; | |
1223 | /// | |
1224 | /// let mut a: HashSet<u32> = vec![1, 2, 3].into_iter().collect(); | |
1225 | /// | |
1226 | /// let mut drain = a.drain(); | |
1227 | /// ``` | |
85aaf69f | 1228 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 1229 | pub struct Drain<'a, K: 'a> { |
1b1a35ee XL |
1230 | base: base::Drain<'a, K>, |
1231 | } | |
1232 | ||
1233 | /// A draining, filtering iterator over the items of a `HashSet`. | |
1234 | /// | |
1235 | /// This `struct` is created by the [`drain_filter`] method on [`HashSet`]. | |
1236 | /// | |
1237 | /// [`drain_filter`]: HashSet::drain_filter | |
1238 | /// | |
1239 | /// # Examples | |
1240 | /// | |
1241 | /// ``` | |
1242 | /// #![feature(hash_drain_filter)] | |
1243 | /// | |
1244 | /// use std::collections::HashSet; | |
1245 | /// | |
1246 | /// let mut a: HashSet<u32> = vec![1, 2, 3].into_iter().collect(); | |
1247 | /// | |
1248 | /// let mut drain_filtered = a.drain_filter(|v| v % 2 == 0); | |
1249 | /// ``` | |
1250 | #[unstable(feature = "hash_drain_filter", issue = "59618")] | |
1251 | pub struct DrainFilter<'a, K, F> | |
1252 | where | |
1253 | F: FnMut(&K) -> bool, | |
1254 | { | |
1255 | base: base::DrainFilter<'a, K, F>, | |
1a4d82fc JJ |
1256 | } |
1257 | ||
cc61c64b XL |
1258 | /// A lazy iterator producing elements in the intersection of `HashSet`s. |
1259 | /// | |
1260 | /// This `struct` is created by the [`intersection`] method on [`HashSet`]. | |
1261 | /// See its documentation for more. | |
1262 | /// | |
3dfed10e | 1263 | /// [`intersection`]: HashSet::intersection |
1b1a35ee XL |
1264 | /// |
1265 | /// # Examples | |
1266 | /// | |
1267 | /// ``` | |
1268 | /// use std::collections::HashSet; | |
1269 | /// | |
1270 | /// let a: HashSet<u32> = vec![1, 2, 3].into_iter().collect(); | |
1271 | /// let b: HashSet<_> = [4, 2, 3, 4].iter().cloned().collect(); | |
1272 | /// | |
1273 | /// let mut intersection = a.intersection(&b); | |
1274 | /// ``` | |
85aaf69f | 1275 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
1276 | pub struct Intersection<'a, T: 'a, S: 'a> { |
1277 | // iterator of the first set | |
1278 | iter: Iter<'a, T>, | |
1279 | // the second set | |
1280 | other: &'a HashSet<T, S>, | |
1281 | } | |
1282 | ||
cc61c64b XL |
1283 | /// A lazy iterator producing elements in the difference of `HashSet`s. |
1284 | /// | |
1285 | /// This `struct` is created by the [`difference`] method on [`HashSet`]. | |
1286 | /// See its documentation for more. | |
1287 | /// | |
3dfed10e | 1288 | /// [`difference`]: HashSet::difference |
1b1a35ee XL |
1289 | /// |
1290 | /// # Examples | |
1291 | /// | |
1292 | /// ``` | |
1293 | /// use std::collections::HashSet; | |
1294 | /// | |
1295 | /// let a: HashSet<u32> = vec![1, 2, 3].into_iter().collect(); | |
1296 | /// let b: HashSet<_> = [4, 2, 3, 4].iter().cloned().collect(); | |
1297 | /// | |
1298 | /// let mut difference = a.difference(&b); | |
1299 | /// ``` | |
85aaf69f | 1300 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
1301 | pub struct Difference<'a, T: 'a, S: 'a> { |
1302 | // iterator of the first set | |
1303 | iter: Iter<'a, T>, | |
1304 | // the second set | |
1305 | other: &'a HashSet<T, S>, | |
1306 | } | |
1307 | ||
cc61c64b XL |
1308 | /// A lazy iterator producing elements in the symmetric difference of `HashSet`s. |
1309 | /// | |
1310 | /// This `struct` is created by the [`symmetric_difference`] method on | |
1311 | /// [`HashSet`]. See its documentation for more. | |
1312 | /// | |
3dfed10e | 1313 | /// [`symmetric_difference`]: HashSet::symmetric_difference |
1b1a35ee XL |
1314 | /// |
1315 | /// # Examples | |
1316 | /// | |
1317 | /// ``` | |
1318 | /// use std::collections::HashSet; | |
1319 | /// | |
1320 | /// let a: HashSet<u32> = vec![1, 2, 3].into_iter().collect(); | |
1321 | /// let b: HashSet<_> = [4, 2, 3, 4].iter().cloned().collect(); | |
1322 | /// | |
1323 | /// let mut intersection = a.symmetric_difference(&b); | |
1324 | /// ``` | |
85aaf69f | 1325 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 1326 | pub struct SymmetricDifference<'a, T: 'a, S: 'a> { |
c30ab7b3 | 1327 | iter: Chain<Difference<'a, T, S>, Difference<'a, T, S>>, |
1a4d82fc JJ |
1328 | } |
1329 | ||
cc61c64b XL |
1330 | /// A lazy iterator producing elements in the union of `HashSet`s. |
1331 | /// | |
1332 | /// This `struct` is created by the [`union`] method on [`HashSet`]. | |
1333 | /// See its documentation for more. | |
1334 | /// | |
3dfed10e | 1335 | /// [`union`]: HashSet::union |
1b1a35ee XL |
1336 | /// |
1337 | /// # Examples | |
1338 | /// | |
1339 | /// ``` | |
1340 | /// use std::collections::HashSet; | |
1341 | /// | |
1342 | /// let a: HashSet<u32> = vec![1, 2, 3].into_iter().collect(); | |
1343 | /// let b: HashSet<_> = [4, 2, 3, 4].iter().cloned().collect(); | |
1344 | /// | |
1345 | /// let mut union_iter = a.union(&b); | |
1346 | /// ``` | |
85aaf69f | 1347 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 1348 | pub struct Union<'a, T: 'a, S: 'a> { |
c30ab7b3 | 1349 | iter: Chain<Iter<'a, T>, Difference<'a, T, S>>, |
1a4d82fc JJ |
1350 | } |
1351 | ||
85aaf69f | 1352 | #[stable(feature = "rust1", since = "1.0.0")] |
9fa01778 | 1353 | impl<'a, T, S> IntoIterator for &'a HashSet<T, S> { |
85aaf69f SL |
1354 | type Item = &'a T; |
1355 | type IntoIter = Iter<'a, T>; | |
1356 | ||
48663c56 | 1357 | #[inline] |
85aaf69f SL |
1358 | fn into_iter(self) -> Iter<'a, T> { |
1359 | self.iter() | |
1360 | } | |
1361 | } | |
1362 | ||
1363 | #[stable(feature = "rust1", since = "1.0.0")] | |
9fa01778 | 1364 | impl<T, S> IntoIterator for HashSet<T, S> { |
85aaf69f SL |
1365 | type Item = T; |
1366 | type IntoIter = IntoIter<T>; | |
1367 | ||
9346a6ac AL |
1368 | /// Creates a consuming iterator, that is, one that moves each value out |
1369 | /// of the set in arbitrary order. The set cannot be used after calling | |
1370 | /// this. | |
1371 | /// | |
1372 | /// # Examples | |
1373 | /// | |
1374 | /// ``` | |
1375 | /// use std::collections::HashSet; | |
1376 | /// let mut set = HashSet::new(); | |
1377 | /// set.insert("a".to_string()); | |
1378 | /// set.insert("b".to_string()); | |
1379 | /// | |
1380 | /// // Not possible to collect to a Vec<String> with a regular `.iter()`. | |
1381 | /// let v: Vec<String> = set.into_iter().collect(); | |
1382 | /// | |
1383 | /// // Will print in an arbitrary order. | |
62682a34 | 1384 | /// for x in &v { |
9346a6ac AL |
1385 | /// println!("{}", x); |
1386 | /// } | |
1387 | /// ``` | |
48663c56 | 1388 | #[inline] |
85aaf69f | 1389 | fn into_iter(self) -> IntoIter<T> { |
1b1a35ee | 1390 | IntoIter { base: self.base.into_iter() } |
85aaf69f SL |
1391 | } |
1392 | } | |
1393 | ||
92a42be0 | 1394 | #[stable(feature = "rust1", since = "1.0.0")] |
9fa01778 | 1395 | impl<K> Clone for Iter<'_, K> { |
48663c56 | 1396 | #[inline] |
9fa01778 | 1397 | fn clone(&self) -> Self { |
1b1a35ee | 1398 | Iter { base: self.base.clone() } |
c30ab7b3 | 1399 | } |
c34b1796 | 1400 | } |
85aaf69f | 1401 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
1402 | impl<'a, K> Iterator for Iter<'a, K> { |
1403 | type Item = &'a K; | |
1404 | ||
48663c56 | 1405 | #[inline] |
c30ab7b3 | 1406 | fn next(&mut self) -> Option<&'a K> { |
1b1a35ee | 1407 | self.base.next() |
c30ab7b3 | 1408 | } |
48663c56 | 1409 | #[inline] |
c30ab7b3 | 1410 | fn size_hint(&self) -> (usize, Option<usize>) { |
1b1a35ee | 1411 | self.base.size_hint() |
c30ab7b3 | 1412 | } |
85aaf69f SL |
1413 | } |
1414 | #[stable(feature = "rust1", since = "1.0.0")] | |
9fa01778 | 1415 | impl<K> ExactSizeIterator for Iter<'_, K> { |
48663c56 | 1416 | #[inline] |
c30ab7b3 | 1417 | fn len(&self) -> usize { |
1b1a35ee | 1418 | self.base.len() |
c30ab7b3 | 1419 | } |
1a4d82fc | 1420 | } |
0531ce1d | 1421 | #[stable(feature = "fused", since = "1.26.0")] |
9fa01778 | 1422 | impl<K> FusedIterator for Iter<'_, K> {} |
1a4d82fc | 1423 | |
8bb4bdeb | 1424 | #[stable(feature = "std_debug", since = "1.16.0")] |
9fa01778 | 1425 | impl<K: fmt::Debug> fmt::Debug for Iter<'_, K> { |
532ac7d7 | 1426 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
cc61c64b | 1427 | f.debug_list().entries(self.clone()).finish() |
32a655c1 SL |
1428 | } |
1429 | } | |
1430 | ||
85aaf69f | 1431 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
1432 | impl<K> Iterator for IntoIter<K> { |
1433 | type Item = K; | |
1434 | ||
48663c56 | 1435 | #[inline] |
c30ab7b3 | 1436 | fn next(&mut self) -> Option<K> { |
1b1a35ee | 1437 | self.base.next() |
c30ab7b3 | 1438 | } |
48663c56 | 1439 | #[inline] |
c30ab7b3 | 1440 | fn size_hint(&self) -> (usize, Option<usize>) { |
1b1a35ee | 1441 | self.base.size_hint() |
c30ab7b3 | 1442 | } |
85aaf69f SL |
1443 | } |
1444 | #[stable(feature = "rust1", since = "1.0.0")] | |
1445 | impl<K> ExactSizeIterator for IntoIter<K> { | |
48663c56 | 1446 | #[inline] |
c30ab7b3 | 1447 | fn len(&self) -> usize { |
1b1a35ee | 1448 | self.base.len() |
c30ab7b3 | 1449 | } |
1a4d82fc | 1450 | } |
0531ce1d | 1451 | #[stable(feature = "fused", since = "1.26.0")] |
9e0c209e | 1452 | impl<K> FusedIterator for IntoIter<K> {} |
1a4d82fc | 1453 | |
8bb4bdeb | 1454 | #[stable(feature = "std_debug", since = "1.16.0")] |
32a655c1 | 1455 | impl<K: fmt::Debug> fmt::Debug for IntoIter<K> { |
532ac7d7 | 1456 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
1b1a35ee | 1457 | fmt::Debug::fmt(&self.base, f) |
32a655c1 SL |
1458 | } |
1459 | } | |
1460 | ||
85aaf69f SL |
1461 | #[stable(feature = "rust1", since = "1.0.0")] |
1462 | impl<'a, K> Iterator for Drain<'a, K> { | |
1a4d82fc JJ |
1463 | type Item = K; |
1464 | ||
48663c56 | 1465 | #[inline] |
c30ab7b3 | 1466 | fn next(&mut self) -> Option<K> { |
1b1a35ee | 1467 | self.base.next() |
c30ab7b3 | 1468 | } |
48663c56 | 1469 | #[inline] |
c30ab7b3 | 1470 | fn size_hint(&self) -> (usize, Option<usize>) { |
1b1a35ee | 1471 | self.base.size_hint() |
c30ab7b3 | 1472 | } |
85aaf69f SL |
1473 | } |
1474 | #[stable(feature = "rust1", since = "1.0.0")] | |
9fa01778 | 1475 | impl<K> ExactSizeIterator for Drain<'_, K> { |
48663c56 | 1476 | #[inline] |
c30ab7b3 | 1477 | fn len(&self) -> usize { |
1b1a35ee | 1478 | self.base.len() |
c30ab7b3 | 1479 | } |
1a4d82fc | 1480 | } |
0531ce1d | 1481 | #[stable(feature = "fused", since = "1.26.0")] |
9fa01778 | 1482 | impl<K> FusedIterator for Drain<'_, K> {} |
1a4d82fc | 1483 | |
8bb4bdeb | 1484 | #[stable(feature = "std_debug", since = "1.16.0")] |
9fa01778 | 1485 | impl<K: fmt::Debug> fmt::Debug for Drain<'_, K> { |
532ac7d7 | 1486 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
1b1a35ee XL |
1487 | fmt::Debug::fmt(&self.base, f) |
1488 | } | |
1489 | } | |
1490 | ||
1491 | #[unstable(feature = "hash_drain_filter", issue = "59618")] | |
1492 | impl<K, F> Iterator for DrainFilter<'_, K, F> | |
1493 | where | |
1494 | F: FnMut(&K) -> bool, | |
1495 | { | |
1496 | type Item = K; | |
1497 | ||
1498 | #[inline] | |
1499 | fn next(&mut self) -> Option<K> { | |
1500 | self.base.next() | |
1501 | } | |
1502 | #[inline] | |
1503 | fn size_hint(&self) -> (usize, Option<usize>) { | |
1504 | self.base.size_hint() | |
1505 | } | |
1506 | } | |
1507 | ||
1508 | #[unstable(feature = "hash_drain_filter", issue = "59618")] | |
1509 | impl<K, F> FusedIterator for DrainFilter<'_, K, F> where F: FnMut(&K) -> bool {} | |
1510 | ||
1511 | #[unstable(feature = "hash_drain_filter", issue = "59618")] | |
1512 | impl<'a, K, F> fmt::Debug for DrainFilter<'a, K, F> | |
1513 | where | |
1514 | F: FnMut(&K) -> bool, | |
1515 | { | |
1516 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { | |
1517 | f.pad("DrainFilter { .. }") | |
32a655c1 SL |
1518 | } |
1519 | } | |
1520 | ||
92a42be0 | 1521 | #[stable(feature = "rust1", since = "1.0.0")] |
9fa01778 | 1522 | impl<T, S> Clone for Intersection<'_, T, S> { |
48663c56 | 1523 | #[inline] |
9fa01778 | 1524 | fn clone(&self) -> Self { |
c34b1796 AL |
1525 | Intersection { iter: self.iter.clone(), ..*self } |
1526 | } | |
1527 | } | |
1528 | ||
85aaf69f SL |
1529 | #[stable(feature = "rust1", since = "1.0.0")] |
1530 | impl<'a, T, S> Iterator for Intersection<'a, T, S> | |
dfeec247 XL |
1531 | where |
1532 | T: Eq + Hash, | |
1533 | S: BuildHasher, | |
1a4d82fc JJ |
1534 | { |
1535 | type Item = &'a T; | |
1536 | ||
48663c56 | 1537 | #[inline] |
1a4d82fc JJ |
1538 | fn next(&mut self) -> Option<&'a T> { |
1539 | loop { | |
ff7c6d11 XL |
1540 | let elt = self.iter.next()?; |
1541 | if self.other.contains(elt) { | |
1542 | return Some(elt); | |
1a4d82fc JJ |
1543 | } |
1544 | } | |
1545 | } | |
1546 | ||
48663c56 | 1547 | #[inline] |
85aaf69f | 1548 | fn size_hint(&self) -> (usize, Option<usize>) { |
1a4d82fc JJ |
1549 | let (_, upper) = self.iter.size_hint(); |
1550 | (0, upper) | |
1551 | } | |
1552 | } | |
1553 | ||
8bb4bdeb | 1554 | #[stable(feature = "std_debug", since = "1.16.0")] |
9fa01778 | 1555 | impl<T, S> fmt::Debug for Intersection<'_, T, S> |
dfeec247 XL |
1556 | where |
1557 | T: fmt::Debug + Eq + Hash, | |
1558 | S: BuildHasher, | |
32a655c1 | 1559 | { |
532ac7d7 | 1560 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
cc61c64b | 1561 | f.debug_list().entries(self.clone()).finish() |
32a655c1 SL |
1562 | } |
1563 | } | |
1564 | ||
0531ce1d | 1565 | #[stable(feature = "fused", since = "1.26.0")] |
9fa01778 | 1566 | impl<T, S> FusedIterator for Intersection<'_, T, S> |
dfeec247 XL |
1567 | where |
1568 | T: Eq + Hash, | |
1569 | S: BuildHasher, | |
c30ab7b3 SL |
1570 | { |
1571 | } | |
9e0c209e | 1572 | |
92a42be0 | 1573 | #[stable(feature = "rust1", since = "1.0.0")] |
9fa01778 | 1574 | impl<T, S> Clone for Difference<'_, T, S> { |
48663c56 | 1575 | #[inline] |
9fa01778 | 1576 | fn clone(&self) -> Self { |
c34b1796 AL |
1577 | Difference { iter: self.iter.clone(), ..*self } |
1578 | } | |
1579 | } | |
1580 | ||
85aaf69f SL |
1581 | #[stable(feature = "rust1", since = "1.0.0")] |
1582 | impl<'a, T, S> Iterator for Difference<'a, T, S> | |
dfeec247 XL |
1583 | where |
1584 | T: Eq + Hash, | |
1585 | S: BuildHasher, | |
1a4d82fc JJ |
1586 | { |
1587 | type Item = &'a T; | |
1588 | ||
48663c56 | 1589 | #[inline] |
1a4d82fc JJ |
1590 | fn next(&mut self) -> Option<&'a T> { |
1591 | loop { | |
ff7c6d11 XL |
1592 | let elt = self.iter.next()?; |
1593 | if !self.other.contains(elt) { | |
1594 | return Some(elt); | |
1a4d82fc JJ |
1595 | } |
1596 | } | |
1597 | } | |
1598 | ||
48663c56 | 1599 | #[inline] |
85aaf69f | 1600 | fn size_hint(&self) -> (usize, Option<usize>) { |
1a4d82fc JJ |
1601 | let (_, upper) = self.iter.size_hint(); |
1602 | (0, upper) | |
1603 | } | |
1604 | } | |
1605 | ||
0531ce1d | 1606 | #[stable(feature = "fused", since = "1.26.0")] |
9fa01778 | 1607 | impl<T, S> FusedIterator for Difference<'_, T, S> |
dfeec247 XL |
1608 | where |
1609 | T: Eq + Hash, | |
1610 | S: BuildHasher, | |
c30ab7b3 SL |
1611 | { |
1612 | } | |
9e0c209e | 1613 | |
8bb4bdeb | 1614 | #[stable(feature = "std_debug", since = "1.16.0")] |
9fa01778 | 1615 | impl<T, S> fmt::Debug for Difference<'_, T, S> |
dfeec247 XL |
1616 | where |
1617 | T: fmt::Debug + Eq + Hash, | |
1618 | S: BuildHasher, | |
32a655c1 | 1619 | { |
532ac7d7 | 1620 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
cc61c64b | 1621 | f.debug_list().entries(self.clone()).finish() |
32a655c1 SL |
1622 | } |
1623 | } | |
1624 | ||
92a42be0 | 1625 | #[stable(feature = "rust1", since = "1.0.0")] |
9fa01778 | 1626 | impl<T, S> Clone for SymmetricDifference<'_, T, S> { |
48663c56 | 1627 | #[inline] |
9fa01778 | 1628 | fn clone(&self) -> Self { |
c34b1796 AL |
1629 | SymmetricDifference { iter: self.iter.clone() } |
1630 | } | |
1631 | } | |
1632 | ||
85aaf69f SL |
1633 | #[stable(feature = "rust1", since = "1.0.0")] |
1634 | impl<'a, T, S> Iterator for SymmetricDifference<'a, T, S> | |
dfeec247 XL |
1635 | where |
1636 | T: Eq + Hash, | |
1637 | S: BuildHasher, | |
1a4d82fc JJ |
1638 | { |
1639 | type Item = &'a T; | |
1640 | ||
48663c56 | 1641 | #[inline] |
c30ab7b3 SL |
1642 | fn next(&mut self) -> Option<&'a T> { |
1643 | self.iter.next() | |
1644 | } | |
48663c56 | 1645 | #[inline] |
c30ab7b3 SL |
1646 | fn size_hint(&self) -> (usize, Option<usize>) { |
1647 | self.iter.size_hint() | |
1648 | } | |
1a4d82fc JJ |
1649 | } |
1650 | ||
0531ce1d | 1651 | #[stable(feature = "fused", since = "1.26.0")] |
9fa01778 | 1652 | impl<T, S> FusedIterator for SymmetricDifference<'_, T, S> |
dfeec247 XL |
1653 | where |
1654 | T: Eq + Hash, | |
1655 | S: BuildHasher, | |
c30ab7b3 SL |
1656 | { |
1657 | } | |
9e0c209e | 1658 | |
8bb4bdeb | 1659 | #[stable(feature = "std_debug", since = "1.16.0")] |
9fa01778 | 1660 | impl<T, S> fmt::Debug for SymmetricDifference<'_, T, S> |
dfeec247 XL |
1661 | where |
1662 | T: fmt::Debug + Eq + Hash, | |
1663 | S: BuildHasher, | |
32a655c1 | 1664 | { |
532ac7d7 | 1665 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
cc61c64b | 1666 | f.debug_list().entries(self.clone()).finish() |
32a655c1 SL |
1667 | } |
1668 | } | |
1669 | ||
92a42be0 | 1670 | #[stable(feature = "rust1", since = "1.0.0")] |
9fa01778 | 1671 | impl<T, S> Clone for Union<'_, T, S> { |
48663c56 | 1672 | #[inline] |
9fa01778 | 1673 | fn clone(&self) -> Self { |
c30ab7b3 SL |
1674 | Union { iter: self.iter.clone() } |
1675 | } | |
c34b1796 AL |
1676 | } |
1677 | ||
0531ce1d | 1678 | #[stable(feature = "fused", since = "1.26.0")] |
9fa01778 | 1679 | impl<T, S> FusedIterator for Union<'_, T, S> |
dfeec247 XL |
1680 | where |
1681 | T: Eq + Hash, | |
1682 | S: BuildHasher, | |
c30ab7b3 SL |
1683 | { |
1684 | } | |
9e0c209e | 1685 | |
8bb4bdeb | 1686 | #[stable(feature = "std_debug", since = "1.16.0")] |
9fa01778 | 1687 | impl<T, S> fmt::Debug for Union<'_, T, S> |
dfeec247 XL |
1688 | where |
1689 | T: fmt::Debug + Eq + Hash, | |
1690 | S: BuildHasher, | |
32a655c1 | 1691 | { |
532ac7d7 | 1692 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
cc61c64b | 1693 | f.debug_list().entries(self.clone()).finish() |
32a655c1 SL |
1694 | } |
1695 | } | |
1696 | ||
85aaf69f SL |
1697 | #[stable(feature = "rust1", since = "1.0.0")] |
1698 | impl<'a, T, S> Iterator for Union<'a, T, S> | |
dfeec247 XL |
1699 | where |
1700 | T: Eq + Hash, | |
1701 | S: BuildHasher, | |
1a4d82fc JJ |
1702 | { |
1703 | type Item = &'a T; | |
1704 | ||
48663c56 | 1705 | #[inline] |
c30ab7b3 SL |
1706 | fn next(&mut self) -> Option<&'a T> { |
1707 | self.iter.next() | |
1708 | } | |
48663c56 | 1709 | #[inline] |
c30ab7b3 SL |
1710 | fn size_hint(&self) -> (usize, Option<usize>) { |
1711 | self.iter.size_hint() | |
1712 | } | |
1a4d82fc JJ |
1713 | } |
1714 | ||
54a0048b SL |
1715 | #[allow(dead_code)] |
1716 | fn assert_covariance() { | |
c30ab7b3 SL |
1717 | fn set<'new>(v: HashSet<&'static str>) -> HashSet<&'new str> { |
1718 | v | |
1719 | } | |
1720 | fn iter<'a, 'new>(v: Iter<'a, &'static str>) -> Iter<'a, &'new str> { | |
1721 | v | |
1722 | } | |
1723 | fn into_iter<'new>(v: IntoIter<&'static str>) -> IntoIter<&'new str> { | |
1724 | v | |
1725 | } | |
dfeec247 XL |
1726 | fn difference<'a, 'new>( |
1727 | v: Difference<'a, &'static str, RandomState>, | |
1728 | ) -> Difference<'a, &'new str, RandomState> { | |
c30ab7b3 SL |
1729 | v |
1730 | } | |
dfeec247 XL |
1731 | fn symmetric_difference<'a, 'new>( |
1732 | v: SymmetricDifference<'a, &'static str, RandomState>, | |
1733 | ) -> SymmetricDifference<'a, &'new str, RandomState> { | |
c30ab7b3 SL |
1734 | v |
1735 | } | |
dfeec247 XL |
1736 | fn intersection<'a, 'new>( |
1737 | v: Intersection<'a, &'static str, RandomState>, | |
1738 | ) -> Intersection<'a, &'new str, RandomState> { | |
c30ab7b3 SL |
1739 | v |
1740 | } | |
dfeec247 XL |
1741 | fn union<'a, 'new>( |
1742 | v: Union<'a, &'static str, RandomState>, | |
1743 | ) -> Union<'a, &'new str, RandomState> { | |
c30ab7b3 SL |
1744 | v |
1745 | } | |
1746 | fn drain<'new>(d: Drain<'static, &'static str>) -> Drain<'new, &'new str> { | |
1747 | d | |
1748 | } | |
54a0048b | 1749 | } |